Generic reactions exactly parallel this representation of mixtures. We can envision a database representation of mixtures which captures this information directly, rather than through the CHUCKLES and CHORTLES languages.
This shifts the burden of describing mixtures to writing comprehensive transformations.
Several groups are experimenting with this idea.
This doesn't seem to be a practical way to store mixtures in a database.
Given the types of questions one wants to ask about mixtures (typically about
the final molecules in the mixture), there would be a lot of pre-computation
required to answer them. More likely is this will serve as the description of
"experimental design", which would be followed by an
enumeration/processing step to generate the database molecules.